Attached drives aren't as useful as they once were. Google (NASDAQ:GOOGL) and Dropbox are part of the problem. Both companies offer online storage that invisibly syncs with a computer's hard drive so that backup is almost an afterthought.

Apple (NASDAQ:AAPL) should be offering an alternative for Mac users, says Tim Beyers of Motley Fool Rule Breakers and Motley Fool Supernova. By committing entirely to the disk-based backup app Time Machine, the iEmpire is foregoing a chance to hook customers on iCloud and in the process holding back what could be a powerful catalyst for an Apple stock rally.

There's little cost to Apple to not acting right now; iCloud is too closely associated with iTunes content while Dropbox and Google Drive both perform well. The Mac maker would have to offer something materially different or better in iCloud in order to get users to switch. But if it did, Tim says, hundreds of millions in annual subscription revenue could be up for grabs.

Do you agree? Watch the video below to get Tim's full take, and then let us know whether you would buy, sell, or short Apple stock at current prices.

Fool contributor Tim Beyers is a member of the Motley Fool Rule Breakers stock-picking team and the Motley Fool Supernova Odyssey I mission. He owned shares of Apple and Google at the time of publication. Check out Tim's web home and portfolio holdings or connect with him on Google+Tumblr, or Twitter, where he goes by @milehighfool. You can also get his insights delivered directly to your RSS reader.

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